226 research outputs found

    Contribution du warrantage à l’accès des petits producteurs au marché des intrants et des produits agricoles dans les communes rurales de Kléla, Fama et Zebala dans la région de Sikasso au Mali

    Get PDF
    Une expérimentation pilote sur le warrantage a été conduite dans la zone d’intervention du projet «Gestion intégrée de l’eau et des éléments nutritifs pour une production agricole durable dans le sahel» ACDI/CRDI au Mali. Ses objectifs étaient d’éviter que le paysan brade sa production immédiatement après les récoltes et d’organiser le marché de manière qu’il puisse tirer profit de la commercialisation de ses produits agricoles tout en s’approvisionnant en intrants agricoles. Elle a été organisée et exécutée dans un partenariat multi acteurs comprenant les institutions de recherche, vulgarisation agricole et producteurs, production de semence, finance, agrodealers et le partenaire financier. Les paysans organisés en coopératives de producteurs ont exécuté le warrantage avec un crédit de 15 millions FCFA et les participants étaient constitués de 12 % de paysans nantis, 32 % de moyennement nantis et 56 % de démunis. Les paysansdémunis et moyennement nantis ont beaucoup plus participé au stockage et ont pu s’approvisionner en engrais dans la boutique d’intrants agricoles. A Siramana, les femmes ont produit l’aubergine Africaine en maraîchage d’hivernage comme activité génératrice de revenu. Elles ont payé le crédit contracté auprès de leurs coopératives avec le bénéfice réalisé sur ces activités. Le warrantage a permis aux femmes et aux petits producteurs d’acheter des engrais dans leurs villages, de participer eux-mêmes à la commercialisation de leurs récoltes et d’entreprendre des activités génératrices de revenu pour davantage améliorer leur revenu agricole. Une perspective de cette activité est présentée.Mots clés : Warrantage, revenu, partenariat, crédit, Sikasso

    LNG vapour cloud dispersion modelling and simulations with OpenFOAM

    Get PDF
    Growth in demand for Liquefied Natural Gas (LNG) has increased calls for further research and development on LNG production and safer methods for its transportation. This paper presents the implementation of numerical models for dispersion of evaporated LNG in the open atmosphere. The developed model incorporates in its formulation LNG spill and pool formation into a source model. It is then coupled with a Computational Fluid Dynamics (CFD) approach in OpenFOAM for dispersion calculations. Atmospheric conditions such as average wind speed and direction were used to resolve wind boundary layers. The model also accounts for the humidity effect and its influence on air-density and buoyancy change. Verifications have been conducted using the experimental results from Maplin Sands series of tests by comparing the maximum evaporated gas concentration in every arc in relation to the release point. The results show good agreements between the model’s predictions and experiments

    Developpement des systemes de production innovants d’association mais/legumineuses dans la zone subhumide du Mali

    Get PDF
    Parmi les 3 piliers de l’intégration agriculture-élevage (traction animale, fumure organique, cultures fourragères) diffusés en Afrique de l’Ouest, seules les cultures fourragères ont été peu adoptées. Pourtant, les associations maïs/légumineuses ont l’avantage d’améliorer la production et l’alimentation animale. Elles représentent une alternative dans la gestion des risques et des incertitudes pour les agro-éleveurs, confrontés aux changements globaux (climatiques, pression foncière, dégradation des ressources naturelles). L’objectif de cette étude est de déterminer la contribution des associations maïs/légumineuses dans l’amélioration de la production de maïs grain et le bilan fourrager des exploitations agricoles. Le dispositif en blocs dispersés chez 10 producteurs, a consisté en 3 traitements, T1 (maïs seul), T2 (maïs/ niébé) et T3 (maïs/mucuna) durant 2 campagnes agricoles. En 2013 - 2014, les rendements de maïs grain ont été de 2433 kg/ha et en biomasse 2597 kgMS/ha. Par contre, en 2014 - 2015 les rendements ont été de 1932 kg/ha de maïs grain et de 5134 kgMS/ha de biomasse. Les besoins en matière sèche pour 90 jours de supplémentation ont été de 4,62 UBT en 2013 - 2014 et de 9,13 UBT en 2014 - 2015. Ces résultats montrent la contribution des associations maïs/légumineuses dans l’amélioration du rendement de maïs grain et de fourrages dans la zone subhumide au Mali.Mots clés : légumineuses, maïs, fourrage, Mal

    Acetabular fractures: epidemiological, lesional, therapeutic and evolutionary aspects

    Get PDF
    Background: Fractures of the acetabulum are serious because they affect a deep, load-bearing joint that is difficult to repair surgically at first. They occur in a context of polytrauma. The aim of our work is to study the epidemiological, lesional, therapeutic and evolutionary aspects of acetabulum fractures.Methods: This is a 5-year retrospective study from January 2012 to December 2016 including 45 patients treated for acetabulum fracture.Results: 45 patients including 38 men and 7 women with a mean age of 36 years (extremes 18 and 74). The circumstances of occurrence were dominated by road traffic accidents with 42 cases (93.3%).According to the Judet-Letournel classification, we observed 28 elementary fractures (16 posterior wall fractures, 11 posterior column fractures, 1 anterior column fracture) and 17 complex fractures (7 posterior column and posterior wall fractures, 6 transverse and posterior wall fractures, 3 posterior and anterior column fractures, 1 anterior column and posterior hemi-transverse fracture). The association of a dislocation with an acetabulum fracture was found in 32 cases. Associated lesions (fractures) were observed in 23 patients. One case of associated TCE was noted. Treatment was orthopedic in 18 patients, surgical in 18 patients and functional in 9 patients. According to the Matta criteria we obtained after treatment 46.7% good reduction, 51.1% satisfactory and 2.2% unsatisfactory reduction. According to the Postel-Merle D'Aubigné rating, 16 patients obtained excellent results with overall 93.3% satisfactory results. The complications found were coxarthrosis (15 cases), para-articular ossification (2 cases) and vicious callus (1 case).Conclusions: The treatment of acetabulum fractures depends on the type of fracture, the age and activities of the patients. Orthopedic, surgical as well as functional treatment can give good acetabular reconstructions and functional results

    SMART: Unique splitting-while-merging framework for gene clustering

    Get PDF
    Copyright @ 2014 Fa et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Successful clustering algorithms are highly dependent on parameter settings. The clustering performance degrades significantly unless parameters are properly set, and yet, it is difficult to set these parameters a priori. To address this issue, in this paper, we propose a unique splitting-while-merging clustering framework, named “splitting merging awareness tactics” (SMART), which does not require any a priori knowledge of either the number of clusters or even the possible range of this number. Unlike existing self-splitting algorithms, which over-cluster the dataset to a large number of clusters and then merge some similar clusters, our framework has the ability to split and merge clusters automatically during the process and produces the the most reliable clustering results, by intrinsically integrating many clustering techniques and tasks. The SMART framework is implemented with two distinct clustering paradigms in two algorithms: competitive learning and finite mixture model. Nevertheless, within the proposed SMART framework, many other algorithms can be derived for different clustering paradigms. The minimum message length algorithm is integrated into the framework as the clustering selection criterion. The usefulness of the SMART framework and its algorithms is tested in demonstration datasets and simulated gene expression datasets. Moreover, two real microarray gene expression datasets are studied using this approach. Based on the performance of many metrics, all numerical results show that SMART is superior to compared existing self-splitting algorithms and traditional algorithms. Three main properties of the proposed SMART framework are summarized as: (1) needing no parameters dependent on the respective dataset or a priori knowledge about the datasets, (2) extendible to many different applications, (3) offering superior performance compared with counterpart algorithms.National Institute for Health Researc

    Dynamics of antigenemia and transmission intensity of Wuchereria bancrofti following cessation of mass drug administration in a formerly highly endemic region of Mali

    Get PDF
    Background After seven annual rounds of mass drug administration (MDA) in six Malian villages highly endemic for Wuchereria bancrofti (overall prevalence rate of 42.7%), treatment was discontinued in 2008. Surveillance was performed over the ensuing 5 years to detect recrudescence. Methods Circulating filarial antigen (CFA) was measured using immunochromatographic card tests (ICT) and Og4C3 ELISA in 6–7 year-olds. Antibody to the W. bancrofti infective larval stage (L3) antigen, Wb123, was tested in the same population in 2012. Microfilaraemia was assessed in ICT-positive subjects. Anopheles gambiae complex specimens were collected monthly using human landing catch (HLC) and pyrethrum spray catch (PSC). Anopheles gambiae complex infection with W. bancrofti was determined by dissection and reverse transcriptase polymerase chain reaction (RT-PCR) of mosquito pools. Results Annual CFA prevalence rates using ICT in children increased over time from 0% (0/289) in 2009 to 2.7% (8/301) in 2011, 3.9% (11/285) in 2012 and 4.5% (14/309) in 2013 (trend χ 2  = 11.85, df =3, P = 0.0006). Wb123 antibody positivity rates in 2013 were similar to the CFA prevalence by ELISA (5/285). Although two W. bancrofti-infected Anopheles were observed by dissection among 12,951 mosquitoes collected by HLC, none had L3 larvae when tested by L3-specific RT-PCR. No positive pools were detected among the mosquitoes collected by pyrethrum spray catch. Whereas ICT in 6–7 year-olds was the major surveillance tool, ICT positivity was also assessed in older children and adults (8–65 years old). CFA prevalence decreased in this group from 4.9% (39/800) to 3.5% (28/795) and 2.8% (50/1,812) in 2009, 2011 and 2012, respectively (trend χ 2  = 7.361, df =2, P = 0.0067). Some ICT-positive individuals were microfilaraemic in 2009 [2.6% (1/39)] and 2011 [8.3% (3/36)], but none were positive in 2012 or 2013. Conclusion Although ICT rates in children increased over the 5-year surveillance period, the decrease in ICT prevalence in the older group suggests a reduction in transmission intensity. This was consistent with the failure to detect infective mosquitoes or microfilaraemia. The threshold of ICT positivity in children may need to be re-assessed and other adjunct surveillance tools considered

    A repurposing strategy for Hsp90 inhibitors demonstrates their potency against filarial nematodes

    Get PDF
    Novel drugs are required for the elimination of infections caused by filarial worms, as most commonly used drugs largely target the microfilariae or first stage larvae of these infections. Previous studies, conducted in vitro, have shown that inhibition of Hsp90 kills adult Brugia pahangi. As numerous small molecule inhibitors of Hsp90 have been developed for use in cancer chemotherapy, we tested the activity of several novel Hsp90 inhibitors in a fluorescence polarization assay and against microfilariae and adult worms of Brugia in vitro. The results from all three assays correlated reasonably well and one particular compound, NVP-AUY922, was shown to be particularly active, inhibiting Mf output from female worms at concentrations as low as 5.0 nanomolar after 6 days exposure to drug. NVP-AUY922 was also active on adult worms after a short 24 h exposure to drug. Based on these in vitro data, NVP-AUY922 was tested in vivo in a mouse model and was shown to significantly reduce the recovery of both adult worms and microfilariae. These studies provide proof of principle that the repurposing of currently available Hsp90 inhibitors may have potential for the development of novel agents with macrofilaricidal properties

    Utilisation des facteurs climatiques pour la surveillance de la fréquence des occurrences de méningite/ paludisme à Bamako

    Get PDF
    Objectif : Notre travail consiste à : Déterminer les périodes de risque pour la méningite et le paludisme à Bamako; Etablir une corrélation entre : - d’une part les paramètres météorologiques (température de l’air, humidité relative de l’air, pluviométrie, insolation et vitesse du vent) et la fréquence des occurrences de paludisme ; - d’autre part les mêmes paramètres pour la méningite. Méthode : Nous avons fait une étude rétrospective de l’évolution du paludisme et de la méningite en fonction de la variation des paramètres météorologiques (température de l’air, humidité relative de l’air, pluviométrie, insolation et vitesse du vent) à Bamako. Résultats : Le paludisme, rare au 1er et 2èm trimestres, est très fréquent au 3è trimestre et au 4è trimestre. Quant à la méningite elle est fréquente au premier semestre et rare pendant le reste de l’année. La fréquence du paludisme est liée à la température moyenne de l’air, à la grande humidité de l’air, à la pluviométrie abondante, à la faible insolation et à la faible vitesse du vent. La fréquente de la méningite est liée à la haute température de l’air, à la faible humidité de l’air, à la faible pluviométrie, à la forte insolation et à la grande vitesse du vent. Conclusion : La fréquence du paludisme est liée à la grande humidité, et à la faible insolation. Quant à la méningite, sa fréquence est liée à la haute température, à la grande vitesse du vent et à la forte insolation

    Analyse multiéchelle de la diversité génétique des sorghos : compréhension des processus évolutifs pour la conservation in situ

    Get PDF
    Using microsatellite genetic markers, we analyzed 1,518 sorghum samples collected at different spatial scales in Burkina Faso, Mali, Niger, and in the village of Wanté, from the landrace to the country scale. Genetic diversity and differentiation parameters were estimated to assess the effects of the main evolutionary processes on sorghum genetic diversity. The genetic variability found within a variety is mainly the result of the sorghum reproduction biology and the genetic drift process caused by the limited number of reproductive individuals at the time of variety introduction into a household or each year when farmers select their seeds. At the village scale, a low correlation is observed between the diversity of vernacular names and the genetic diversity assessed by microsatellites. No spatial genetic structuration is observed among villages more than 30 kilometers apart. This point highlights that traditional seed systems operate at a very local scale. In Mali, a similar proportion of allelic richness is observed along a longitudinal transect and a latitudinal gradient that crosses a larger range of agroclimatic conditions. At the country scale, sorghum exhibits more genetic diversity in Niger than in Mali despite a lower agroclimatic range in Niger. These results demonstrate that the diversity of human groups acts together with the agro-ecological factors to shape the structure of sorghum genetic diversity. An important proportion of the overall genetic diversity present in the Cirad (Centre de coopération internationale en recherche agronomique pour le développement) "core collection" is found in Mali and Niger. The tremendous diversity cultivated by farmers in traditional agroecosystems of Western Africa supports the relevance of in situ approaches for sorghum conservation programs in this region. Both conservation and crop improvement requirements can be achieved through a better use of local germplasm in decentralized breeding programs. (Summary in English)
    • …
    corecore